What is the basic structure of the casing head?

The casing head is generally made of 35 or 42 chromium molybdenum high-quality alloy structural steel. A casing hanger is also installed inside the casing head to suspend the corresponding specifications of the casing string and seal the annular space gap. It needs to be equipped with a blowout preventer group. After the oil well is completed, a Christmas tree is installed on the casing head.